ABSTRACT: It is well established that clinicians cannot use clinical
judgment alone to determine whether an individual patient who presents
to the emergency department has an acute coronary syndrome. The
history and physical examination do not distinguish sufficiently between
the many conditions that can cause acute chest pain syndromes. Cardiac
risk factors do not have sufficient discriminatory ability in symptomatic
patients presenting to the emergency department. Most patients with
non–ST-segment–elevation myocardial infarction do not present with
electrocardiographic evidence of active ischemia. The improvement in
cardiac troponin assays, especially in conjunction with well-validated clinical
decision algorithms, now enables the clinician to rapidly exclude myocardial
infarction. In patients in whom unstable angina remains a concern or there
is a desire to evaluate for underlying coronary artery disease, coronary
computed tomography angiography can be used in the emergency
department. Once a process that took ≥24 hours, computed tomography
angiography now can rapidly exclude myocardial infarction and coronary
artery disease in patients in the emergency department."